I know the bore and stroke of a 340. My point is everyone that stays behind the 340 in a A-body while the 383 is pulling more weight and cutting more wind. As far as the BB in a A-body, I think the exhaust got some choked..... But put them both in a 3000 lbs car with the same 3.55's and open headers, I think the 383 takes the win on a 340. And I love 340's
